Question One

data("cars")
median(cars$speed)
## [1] 15

Question 2

On_Time_Performance <- read.csv("~/Downloads/Mini Project-2/On_Time_Performance.csv", header=FALSE)
head(On_Time_Performance)
##     V1      V2    V3         V4        V5         V6            V7        V8
## 1 Year Quarter Month DayofMonth DayOfWeek FlightDate UniqueCarrier AirlineID
## 2 2018       1     1         16         2 2018-01-16            AA     19805
## 3 2018       1     1         17         3 2018-01-17            AA     19805
## 4 2018       1     1         18         4 2018-01-18            AA     19805
## 5 2018       1     1         19         5 2018-01-19            AA     19805
## 6 2018       1     1         20         6 2018-01-20            AA     19805
##        V9     V10       V11             V12                V13
## 1 Carrier TailNum FlightNum OriginAirportID OriginAirportSeqID
## 2      AA  N128AN       228           12892            1289206
## 3      AA  N128AN       228           12892            1289206
## 4      AA  N121AN       228           12892            1289206
## 5      AA  N129AA       228           12892            1289206
## 6      AA  N133AN       228           12892            1289206
##                  V14    V15             V16         V17             V18
## 1 OriginCityMarketID Origin  OriginCityName OriginState OriginStateFips
## 2              32575    LAX Los Angeles, CA          CA              06
## 3              32575    LAX Los Angeles, CA          CA              06
## 4              32575    LAX Los Angeles, CA          CA              06
## 5              32575    LAX Los Angeles, CA          CA              06
## 6              32575    LAX Los Angeles, CA          CA              06
##               V19       V20           V21              V22              V23
## 1 OriginStateName OriginWac DestAirportID DestAirportSeqID DestCityMarketID
## 2      California        91         12173          1217303            32134
## 3      California        91         12173          1217303            32134
## 4      California        91         12173          1217303            32134
## 5      California        91         12173          1217303            32134
## 6      California        91         12173          1217303            32134
##    V24          V25       V26           V27           V28     V29        V30
## 1 Dest DestCityName DestState DestStateFips DestStateName DestWac CRSDepTime
## 2  HNL Honolulu, HI        HI            15        Hawaii       2       2011
## 3  HNL Honolulu, HI        HI            15        Hawaii       2       2011
## 4  HNL Honolulu, HI        HI            15        Hawaii       2       2011
## 5  HNL Honolulu, HI        HI            15        Hawaii       2       2011
## 6  HNL Honolulu, HI        HI            15        Hawaii       2       2011
##       V31      V32             V33      V34                  V35        V36
## 1 DepTime DepDelay DepDelayMinutes DepDel15 DepartureDelayGroups DepTimeBlk
## 2    2010    -1.00            0.00     0.00                   -1  2000-2059
## 3    2003    -8.00            0.00     0.00                   -1  2000-2059
## 4    2008    -3.00            0.00     0.00                   -1  2000-2059
## 5    2010    -1.00            0.00     0.00                   -1  2000-2059
## 6    2001   -10.00            0.00     0.00                   -1  2000-2059
##       V37       V38      V39    V40        V41     V42      V43             V44
## 1 TaxiOut WheelsOff WheelsOn TaxiIn CRSArrTime ArrTime ArrDelay ArrDelayMinutes
## 2   24.00      2034     2358   7.00       0029    0005   -24.00            0.00
## 3   18.00      2021     2348   5.00       0029    2353   -36.00            0.00
## 4   14.00      2022     0006   6.00       0029    0012   -17.00            0.00
## 5   17.00      2027     2352   3.00       0029    2355   -34.00            0.00
## 6   17.00      2018     2352   5.00       0029    2357   -32.00            0.00
##        V45                V46        V47       V48              V49      V50
## 1 ArrDel15 ArrivalDelayGroups ArrTimeBlk Cancelled CancellationCode Diverted
## 2     0.00                 -2  0001-0559      0.00                      0.00
## 3     0.00                 -2  0001-0559      0.00                      0.00
## 4     0.00                 -2  0001-0559      0.00                      0.00
## 5     0.00                 -2  0001-0559      0.00                      0.00
## 6     0.00                 -2  0001-0559      0.00                      0.00
##              V51               V52     V53     V54      V55           V56
## 1 CRSElapsedTime ActualElapsedTime AirTime Flights Distance DistanceGroup
## 2         378.00            355.00  324.00    1.00  2556.00            11
## 3         378.00            350.00  327.00    1.00  2556.00            11
## 4         378.00            364.00  344.00    1.00  2556.00            11
## 5         378.00            345.00  325.00    1.00  2556.00            11
## 6         378.00            356.00  334.00    1.00  2556.00            11
##            V57          V58      V59           V60               V61
## 1 CarrierDelay WeatherDelay NASDelay SecurityDelay LateAircraftDelay
## 2                                                                   
## 3                                                                   
## 4                                                                   
## 5                                                                   
## 6                                                                   
##            V62           V63             V64                V65            V66
## 1 FirstDepTime TotalAddGTime LongestAddGTime DivAirportLandings DivReachedDest
## 2                                                             0               
## 3                                                             0               
## 4                                                             0               
## 5                                                             0               
## 6                                                             0               
##                    V67         V68         V69         V70           V71
## 1 DivActualElapsedTime DivArrDelay DivDistance Div1Airport Div1AirportID
## 2                                                                       
## 3                                                                       
## 4                                                                       
## 5                                                                       
## 6                                                                       
##                V72          V73            V74              V75           V76
## 1 Div1AirportSeqID Div1WheelsOn Div1TotalGTime Div1LongestGTime Div1WheelsOff
## 2                                                                            
## 3                                                                            
## 4                                                                            
## 5                                                                            
## 6                                                                            
##           V77         V78           V79              V80          V81
## 1 Div1TailNum Div2Airport Div2AirportID Div2AirportSeqID Div2WheelsOn
## 2                                                                    
## 3                                                                    
## 4                                                                    
## 5                                                                    
## 6                                                                    
##              V82              V83           V84         V85         V86
## 1 Div2TotalGTime Div2LongestGTime Div2WheelsOff Div2TailNum Div3Airport
## 2                                                                      
## 3                                                                      
## 4                                                                      
## 5                                                                      
## 6                                                                      
##             V87              V88          V89            V90              V91
## 1 Div3AirportID Div3AirportSeqID Div3WheelsOn Div3TotalGTime Div3LongestGTime
## 2                                                                            
## 3                                                                            
## 4                                                                            
## 5                                                                            
## 6                                                                            
##             V92         V93         V94           V95              V96
## 1 Div3WheelsOff Div3TailNum Div4Airport Div4AirportID Div4AirportSeqID
## 2                                                                     
## 3                                                                     
## 4                                                                     
## 5                                                                     
## 6                                                                     
##            V97            V98              V99          V100        V101
## 1 Div4WheelsOn Div4TotalGTime Div4LongestGTime Div4WheelsOff Div4TailNum
## 2                                                                       
## 3                                                                       
## 4                                                                       
## 5                                                                       
## 6                                                                       
##          V102          V103             V104         V105           V106
## 1 Div5Airport Div5AirportID Div5AirportSeqID Div5WheelsOn Div5TotalGTime
## 2                                                                       
## 3                                                                       
## 4                                                                       
## 5                                                                       
## 6                                                                       
##               V107          V108        V109 V110
## 1 Div5LongestGTime Div5WheelsOff Div5TailNum   NA
## 2                                              NA
## 3                                              NA
## 4                                              NA
## 5                                              NA
## 6                                              NA

Question 3

sum(is.na(On_Time_Performance$WheelsOff))
## [1] 0

Question 4

library(dplyr)
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
data <- read.csv("~/Downloads/Mini Project-2/On_Time_Performance.csv")
colnames(On_Time_Performance)
##   [1] "V1"   "V2"   "V3"   "V4"   "V5"   "V6"   "V7"   "V8"   "V9"   "V10" 
##  [11] "V11"  "V12"  "V13"  "V14"  "V15"  "V16"  "V17"  "V18"  "V19"  "V20" 
##  [21] "V21"  "V22"  "V23"  "V24"  "V25"  "V26"  "V27"  "V28"  "V29"  "V30" 
##  [31] "V31"  "V32"  "V33"  "V34"  "V35"  "V36"  "V37"  "V38"  "V39"  "V40" 
##  [41] "V41"  "V42"  "V43"  "V44"  "V45"  "V46"  "V47"  "V48"  "V49"  "V50" 
##  [51] "V51"  "V52"  "V53"  "V54"  "V55"  "V56"  "V57"  "V58"  "V59"  "V60" 
##  [61] "V61"  "V62"  "V63"  "V64"  "V65"  "V66"  "V67"  "V68"  "V69"  "V70" 
##  [71] "V71"  "V72"  "V73"  "V74"  "V75"  "V76"  "V77"  "V78"  "V79"  "V80" 
##  [81] "V81"  "V82"  "V83"  "V84"  "V85"  "V86"  "V87"  "V88"  "V89"  "V90" 
##  [91] "V91"  "V92"  "V93"  "V94"  "V95"  "V96"  "V97"  "V98"  "V99"  "V100"
## [101] "V101" "V102" "V103" "V104" "V105" "V106" "V107" "V108" "V109" "V110"
avg_delay_by_carrier <- data %>%
  group_by(Carrier) %>%
  summarise(avg_departure_delay = mean(DepDelay, na.rm = TRUE))

avg_delay_by_carrier
## # A tibble: 18 × 2
##    Carrier avg_departure_delay
##    <chr>                 <dbl>
##  1 9E                    12.4 
##  2 AA                     6.93
##  3 AS                    -2.25
##  4 B6                    20.4 
##  5 DL                     9.74
##  6 EV                    13.6 
##  7 F9                    16.0 
##  8 G4                    10.4 
##  9 HA                     1.72
## 10 MQ                     8.82
## 11 NK                     5.61
## 12 OH                    13.8 
## 13 OO                    15.1 
## 14 UA                     5.87
## 15 VX                     2.83
## 16 WN                     8.03
## 17 YV                     8.86
## 18 YX                     7.26
largest_delay_by_carrier  <- avg_delay_by_carrier %>%
  arrange(desc(avg_departure_delay)) %>%
  head(1)

largest_delay_by_carrier
## # A tibble: 1 × 2
##   Carrier avg_departure_delay
##   <chr>                 <dbl>
## 1 B6                     20.4

Question 5

library(jsonlite)
library(httr)

url <-  "https://min-api.cryptocompare.com/data/v2/histoday?fsym=BTC&tsym=USD&limit=100"
data <- fromJSON(url)
ohlcv_data <-data$Data$Data
close_prices <- ohlcv_data$close 
str(close_prices)
##  num [1:101] 91904 95958 95670 97511 96474 ...
closse_prices <- as.numeric(close_prices)
max_close_price <- max(close_prices, na.rm = TRUE)
max_close_price
## [1] 106155.6